Fluid compressor



jupe 22, 1937. "B. s. AIKMAN FLUID COMPRESSOR Filed March 27, 1956 42 47 m 2 55 57 [I I 5| INVENTOR BURTON S- AIRMAN ATTORN EY Patented June 22, 1937 'UNITED STATES P T NifosFice' FLUID COMPRESSOR Burton s. Aikman, Wilkinsb'urg,Pa., assig'norto The Westinghouse Air Brake Company, Wil-' p merding, Pa., a corporation of lennsylva'nia" Application March 2'7, 1936,, SerialNo. 71,22 2 7 l 3 v 4 .5.

. This invention relates to fluid compressors, particularly to air cooled compressors, and the principal object of the invention is to provide a simple and inexpensive arrangement for effectively cooling a compressor.

The above and other objects and advantages of the'invention made apparent hereinafter are attained by an illustrative embodiment of the invention, subsequently to be described, and

10 shown in the accompanying drawing wherein,

' Fig. 1 is a vertical sectional view of a compressor'embodying my invention, and Fig. 2 is a fragmentary view taken on the. line -2--2 of Fig. 1, showing a detail of the fan construction.

As shown in Fig. l, the compressor has a sectional casing comprising a crank case section '3yan'end section 4, and a compression cylinder section 5. The crank case section 3 has a securing flange 6 at one end thereof, whereby the compressor casing is removably secured to the endface of the casing of a driving motor I, .as by "bolts *or screws 8. It will be noted that the "usual end section of the motor casing containing 'fl'a bearing for supporting one end of the motor armature shaft II' is not required, because a suitable bearing 9 for the motor shaft is provided in a recess l2 in the casing section 3.

The-end of the motor shaft ll extends into athe crank case chamber l3 and has secured thereto, as by a key l4, a tubular crank shaft [l5 having an eccentric l6 and counterweight l1. 'The end section 4 of the compressor casing is secured, as by bolts or screws l9, to the section Il 3'to close the end opening 2| in the section 3 opposite the end flange 6, the casing section 4 I being provided with a suitable journal 22 for supporting the tubular crank shaft of the compressor.

60 The end of the compressor crank shaft l5 extends beyond the outer end of the journal 22 and a driving means, such as the pulley wheel 25, is secured thereto as by a key 24, for a purpose hereinafter made apparent.

The upper portion of the. crank case section 3 is cylindrical in form and has a bore 26 in which the lower portion of the piston 21 of the compressor is guided. A connecting rod 28 of suitable construction, is provided for connecting the wrist pin 29, associated with the piston 21, and the eccentric IS on the crank shaft l5, the lower end of the connecting rod 28 having a downwardly projecting splash finger or rod 3| 55 adapted to pass through the fluid lubricant conextending upwardly is -A aipe-fitting'v 43 provided with threads 44 at one end thereof is threaded into 40 the projection 4| in sealed relation thereto and tained in the lower portion of the crank case chamber l3.-

The .compression cylinder section 5 is pro.- vided with'a flange which is suitably secured to a corresponding flange at theupper end of the.

crank case section 3, asby boltsor screws 33,

.35 to the-crank .casechamber [3 during the compression-stroke of thepiston. and to .permit flow .of fluidundenpressure from the crank case chamber into thecompression chamber during the intake strokeofth'episton. .Thecheck valve device :31 in the: piston 21., it should be understood-is .notra part ofmy present invention, it

being shown merely for the. purpose of illustrating some means forproviding a partial vacuum inthecrank case chamber l3 whereby the posg5 sibility-of leakage ofv oil from the crank case section 3 is minimized, f

A plurality-ofintakeports 38 in thegwall of the bore 34-are unc'overedby the piston, when it is adjacent the-.lowerextremity of its stroke, to admit air into the. compression chamber 35.

The crank-case section. 3v has suitable openings 39 in theflange thereof 'to open the ports 38 to r the atmosphere.

Formed on the top of the casing section 5 and .135

a hollow internally threaded projection 4| within which the discharge valve 42 of the compressor is contained. external a coil spring 45, interposed between the inner end of the pipe-fitting 43 and the discharge .valvei'42, yieldin'gly urges the valve 42 into seated relation on aniannular rib seat 46 SUI-1,45 rounding. the. discharge port 4! leading out'of the compression chamber A discharge pipe 48 threaded intothe-upper' or outer end of the pipe-fitting 43 serves .to. conduct thecompressed air or. fluid tov a suitable receiver or other equip- ,50

flange portion of the crank case section 3 and the compression cylinder casing section 5, and an outer portion 53 of larger diameter, a plurality of radially extending fan blades 54 being secured at the outer ends thereof, as by welding, to the shell 5| within the portion 53, and at the inner ends thereof to a ring 55.

The shell 5| is rotatably supported in depending relation from a. shoulder or flange 56 on the pipe-fitting 43, the inner ring 55 having a bearing member, such as the ball bearing 51,;se-

cured therewithin, as by a press fit.

The shell 5| may be connected to and rota.- tively driven by the compressor crank shaft in any suitable manner, asby means of a beveled clutch wheel or idler pulley 59 interposed between the lower beveled end of the shell 5|l and a beveled face 6| on the pulley wheel 25 attached to the compressor crank shaft l5.

The beveled clutch wheel 59 is rotatably mounted, as on a pin 62 having threads on the end thereof for screwing the pin 62 into a tapped hole 63 at the upper end of the casing section 4. The clutch face of the wheel 59 is provided with a suitable facing 69 of frictional material. A coil spring 65, interposed between the hub portion of the beveled wheel 59 and a flange or head 66 on the'pin 62, yieldingly urges the beveled wheel 59 into frictional contact with the shell 5| and the pulley wheel 25, the tension of the spring 65 being adjustable by turning the pin 62. A bearing member, such as the ball bearing 68, serves to mount the hub of the beveled wheel 59 on the pin 62 and surrounds. the pin 62 loosely enough to permit the beveled wheel 59 to be cocked from a position normal to the axis of the pin and thereby adjust itself. to irregularities of rotation of the shell 5| and of the wheel 25.

A baflle member or deflector 69,. of conical shape, is suitably secured within the lower portion 52 of the shell 5| as by welding the lower wide end thereof to the shell 5|, for the: purpose of directing the cooling air flowing through'the shell 5| against the outer surface of the casing section 5 and between successive vertical radially extending cooling flns integrally formed on or secured to the casing section 5..

In operation, the motor 1 drives the crank shaft 5 of the compressor directly and the piston 2! of the compressor is accordingly reciprocated in the compression chamber bore 34. Air is drawn, by suction, into the compressor chamber 35 through the openings 39 in the casing section 3 and through the intake ports 38 in the casing section 5, and is discharged from the. compressor chamber 35, on the upstroke of the piston, past the dischargev valve 42 to the pipe 48.

Simultaneously, the shell 5| and the fan blades 54 are rotated, and cause flow of cooling air upwardly through the shell. 5| completely encircling the upper cylindrical portion of the crank case section 3 and the compression cylinder casing section 5. The cooling air flowing upwardly through the interior of the shell 5| is directed forcibly against the outer surface of the compression cylinder casing section 5 and between successive fins 1| by thedeflector member, 69, the heated air being ultimately expelled out of shell 5| upwardly from the fan'blades 54.v

It will be understood that the. upper open end of the shell 5| may be provided with: a suitable screen for protection purposes.

The advantages of the particular arrangement, construction and operation of the, cooling fan device which I have devised arethat it is simple and inexpensive to manufacture, rugged and dependable in service, and highly eflective in cooling due to the concentration of the cooling air in close contact with and in encircling relation to the compression cylinder.

While but one embodiment of my invention has been described and shown, it will be understood that various omissions, additions or changes may be made therein without departing from the spirit of my invention and it is therefore not my 0 intention to limit the scope of my invention except as necessitated by the prior art.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is 15 1. A fluid compressor comprising a cylinder having a chamber in which fluid is compressed, a tubular shell concentrically surrounding and rotatably mounted on the said cylinder, and fan blades secured to the interior of the tubular shell 20 7 adapted tocause flow of cooling air axially through said shell and past said cylinder in encircling relation thereto upon rotation. of. said Shell. 1 J

2. A fluid compressor comprising a cylinder 5 having a compression chamber, a piston operat ing in said cylinder for compressing fluid in the chamber, a crank shaft for operating the piston, a tubular shell concentrically surroundingand rotatably mounted on the said cylinder, fan, -,30 blades secured to the interior of the tubular. shell adapted to cause flow of cooling air axially through said shell and past said cylinder in encircling relation thereto upon rotation of said shell, and means connecting the crankshaft, and; 35 shell for rotating said shell upon rotation of the crank shaft. I d 1 r r 3. A fluid compressor comprising a-cylinder having a chamber in which fluid is compressed,

a tubular shell concentricallysurrounding the said cylinder, radially extending fanblades se-""" cured at the outer endsthereof to the interior of said shell and rotatably supported at theinner ends thereof on said cylinder, and mean'sfor rotating said shell and blades tocause flow'of to1-,, ing air axially through the shell and past the said cylinder in encircling relationtheretok 4. A fluid compressor comprising a cylinder having a chamber in which fluid is'compressed, a hollow extension at one end of. said cylinder providing a passage through which fluid compressed in the chamber isdischar'ged therefrom,

a tubular shell concentrically surroundingsai d cylinder, radially extending fan blades secured. at the outer ends thereof to the interior of said shell and supported at the inner ends thereof, on" the said extension for rotation about the axis of the extension, and meansfor rotating said, shell and fan blades to cause flow of cooling air axially through said shell and past said cylinder in encircling relation thereto.

5. A fluid compressor comprising a cylinder having a chamber in which fluid is compressed,

a tubular shell concentrically surrounding and rotatably mounted onthe said cylinder, fan blades secured to the interior of the tubular shell adapted to cause flow of cooling air axially through said shell and past said cylinder in encircling relation thereto upon rotation of said shell, and a deflector secured to the interiorof said shell fQI'QgY directing the cooling air flowing through the shel into close contact. with the said cylinder. T. T r

6. A fluid compressor comprising a casing'having a cylinder forming a compressionqchamber,

a pistonv operative in the chamberzto compress,

fluid, a crank case chamber in said casing, a crank shaft Within the said crank case chamber for reciprocating the piston, said crank shaft extending at one end out of said casing, a tubular shell concentrically surrounding the said cylinder and rotatably mounted thereon, fan blades secured to the interior of said shell adapted to cause flow of cooling air axially through the shell and past said cylinder in encircling relation thereto upon rotation of said shell, and means providing a driving connection between the exterior end of said crank shaft and said shell for effecting rotation of the shell upon rotation of the crank Y shaft.

7. A fluid compressor comprising a casing having a cylinder forming a compression chamber, a piston operative in the chamber to compress fluid, a crank case chamber in said casing, a crank shaft within the said crank case chamber for reciprocating the piston, said crank shaft extending at one end out of said casing, a tubular shell concentrically surrounding the said cylinder and. rotatably mounted thereon, said shell having an annular friction surface thereon, fan blades secured to the interior of said shell adapted to cause flow of cooling air axially through the shell and past said cylinder in encircling relation thereto upon rotation of said shell, a wheel secured to the exterior end of the crank shaft and having a peripheral friction surface thereon, and an idler wheel frictionally engaging the annular friction surface on the shell and the friction surface on the said wheel at the end of the crank shaft for providing a driving connection between the crank shaft and the shell.

BURTON S. AIKMAN. 

